A dental implant fixture is used as a foundation for artificial teeth construction. It is a small post usually made of titanium that acts as a root structure for holding a prosthetic tooth.
It is known in the art to attach a dental prosthesis (crown, bridge of other dental appliances) to a patient's jaw using a dental implant fixture embedded in the patient's jaw. Between the dental implant fixture and the prosthesis a dental abutment is placed, serving as a mediator. One end of the dental abutment is fixed to the dental implant fixture, either internally or externally, while the other end is fixed to the prosthesis (normally inside the prosthetic tooth, in the form of a dental abutment). Collectively, the dental implant fixture, dental abutment, and the mechanism connecting the dental abutment to the assembly are called an implant assembly.
A dental implant fixture can be placed in the upper or the lower jaw bone, and after the bone has grown around the dental implant fixture, the dental implant fixture can hold a crown, a bridge or an over-denture just like roots hold natural teeth in place.
A key to dental implant fixture success is the quantity and quality of the bone where the dental implant fixture is to be positioned. In some patients, particularly in elderly people, the jaw bone may become thinner making it difficult to find a place for dental implants.
To overcome this difficulty, Paulo Malo from Nobel Biocare introduced the concept of “All-On-Four” which is a treatment solution based on four implants positioned on an elevated section of a retreating jawbone to obtain optimal positioning and support for a complete prosthetic denture. More specifically, the “All-On-Four” technique is based on tilting the two distal implants (typically of a total of four implants), which are implanted at the sides of the elevated section of the jawbone at an angle with respect to the jawbone and with respect to the remaining implants, so as to present an aligned and leveled foundation for a dental bridge or similar dental appliance.